文章來源:國家電(dian)網公司 發(fa)布(bu)時間(jian):2009-12-05
11月29日(ri),國(guo)家電(dian)(dian)網公司在(zai)±500千伏三峽送出龍(long)泉—政(zheng)平直(zhi)(zhi)流系統,進行(xing)了(le)首例超高壓直(zhi)(zhi)流輸電(dian)(dian)系統現場融(rong)冰(bing)方(fang)式(shi)試驗(yan)。此前處于(yu)研究階(jie)段的融(rong)冰(bing)運(yun)行(xing)方(fang)式(shi)在(zai)實際(ji)工程上(shang)得到成功驗(yan)證,試驗(yan)填補了(le)國(guo)內外超高壓直(zhi)(zhi)流融(rong)冰(bing)方(fang)式(shi)運(yun)行(xing)的空白。
年(nian)初發(fa)生(sheng)嚴重(zhong)冰災后,國(guo)家電(dian)網公司積極實施科技防災減災,組織有關單位(wei)及(ji)設備(bei)制造企業(ye)開展深(shen)入研究(jiu),決定利(li)用直流(liu)輸電(dian)系(xi)統(tong)(tong)可(ke)靈活(huo)控(kong)制功率(lv)方(fang)(fang)向及(ji)潮(chao)流(liu)的(de)特(te)點,實現直流(liu)輸電(dian)系(xi)統(tong)(tong)的(de)融(rong)冰方(fang)(fang)式(shi)(shi)(shi)運(yun)行。目(mu)前,融(rong)冰方(fang)(fang)式(shi)(shi)(shi)已順利(li)完成了(le)理論研究(jiu)、仿真(zhen)試驗和現場(chang)試驗,在不(bu)增(zeng)加、不(bu)改動任(ren)何一(yi)次設備(bei)的(de)情況下,適當修(xiu)改實際直流(liu)輸電(dian)系(xi)統(tong)(tong)控(kong)制軟件,創新運(yun)行方(fang)(fang)式(shi)(shi)(shi),驗證了(le)已投運(yun)的(de)各(ge)超(chao)高壓直流(liu)輸電(dian)系(xi)統(tong)(tong)均具備(bei)融(rong)冰方(fang)(fang)式(shi)(shi)(shi)運(yun)行條件。
據(ju)了解,11月29日(ri)成功(gong)完成的首(shou)例超高壓(ya)(ya)直(zhi)流(liu)(liu)輸(shu)電融(rong)冰(bing)(bing)方式(shi)試驗,在±500千(qian)伏(fu)龍政(zheng)直(zhi)流(liu)(liu)系(xi)統先后進行(xing)了融(rong)冰(bing)(bing)方式(shi)啟(qi)(qi)動(dong)、模(mo)擬線路(lu)故(gu)(gu)障再啟(qi)(qi)動(dong)、模(mo)擬單極故(gu)(gu)障停運(yun)(yun)、全壓(ya)(ya)運(yun)(yun)行(xing)下電流(liu)(liu)升(sheng)至額(e)定3000安(an)培運(yun)(yun)行(xing)、全壓(ya)(ya)運(yun)(yun)行(xing)下5%過負荷運(yun)(yun)行(xing)、一極降壓(ya)(ya)一極全壓(ya)(ya)不對稱運(yun)(yun)行(xing)、雙極降壓(ya)(ya)運(yun)(yun)行(xing)等試驗,各項性(xing)能(neng)指標正(zheng)常。試驗結果表明,龍政(zheng)直(zhi)流(liu)(liu)輸(shu)電系(xi)統可以(yi)安(an)全應用(yong)新融(rong)冰(bing)(bing)方式(shi),電源側僅需(xu)(xu)提供(gong)15萬~20萬千(qian)瓦的融(rong)冰(bing)(bing)功(gong)率,即可實現原(yuan)先需(xu)(xu)要(yao)滿功(gong)率運(yun)(yun)行(xing)才(cai)能(neng)達到的效果。直(zhi)流(liu)(liu)線路(lu)測(ce)溫(wen)結果表明,額(e)定電流(liu)(liu)運(yun)(yun)行(xing)可以(yi)有效提高線路(lu)溫(wen)升(sheng),在環境(jing)溫(wen)度10~19攝(she)氏度的情況下,導線平均溫(wen)升(sheng)為6~8攝(she)氏度。
此(ci)次試驗由國家電(dian)網公(gong)司(si)(si)(si)建運(yun)部組織中國電(dian)力(li)科(ke)學研究院、國網運(yun)行(xing)(xing)有(you)限公(gong)司(si)(si)(si)、湖(hu)北(bei)省(sheng)(sheng)電(dian)力(li)公(gong)司(si)(si)(si)、安徽省(sheng)(sheng)電(dian)力(li)公(gong)司(si)(si)(si)、北(bei)京(jing)網聯(lian)(lian)直流工程(cheng)技術有(you)限公(gong)司(si)(si)(si)和中南電(dian)力(li)設(she)計院及ABB公(gong)司(si)(si)(si)等聯(lian)(lian)合進行(xing)(xing)。
11月30日(ri)、12月2日(ri),國家電網(wang)公司分別在(zai)宜華(三(san)峽—上海)直(zhi)(zhi)流系(xi)統(tong)、江城(三(san)峽—廣東)直(zhi)(zhi)流系(xi)統(tong)進行了此項試驗。這種(zhong)新型融冰方式,將在(zai)冬季惡劣氣候條件下對直(zhi)(zhi)流輸電線路起到重要保障作(zuo)用。
鏈接
直(zhi)流(liu)輸(shu)(shu)電(dian)(dian)(dian)系(xi)統(tong)通(tong)常應用于遠距離、大容(rong)量輸(shu)(shu)電(dian)(dian)(dian)。常規直(zhi)流(liu)輸(shu)(shu)電(dian)(dian)(dian)系(xi)統(tong)額定輸(shu)(shu)送(song)功率可(ke)達(da)到300萬千瓦,額定輸(shu)(shu)送(song)電(dian)(dian)(dian)流(liu)3000安培(pei)。當處于大電(dian)(dian)(dian)流(liu)運行時(shi),電(dian)(dian)(dian)流(liu)在(zai)導線上產生的熱量可(ke)以(yi)緩(huan)解線路(lu)覆冰(bing)(bing),達(da)到一定融冰(bing)(bing)效果。但冰(bing)(bing)雪(xue)災(zai)害易發(fa)時(shi)期(qi)多是水(shui)電(dian)(dian)(dian)枯水(shui)季,輸(shu)(shu)電(dian)(dian)(dian)系(xi)統(tong)難以(yi)安排足(zu)夠功率使直(zhi)流(liu)輸(shu)(shu)電(dian)(dian)(dian)系(xi)統(tong)運行大電(dian)(dian)(dian)流(liu)工況,因此線路(lu)輸(shu)(shu)送(song)電(dian)(dian)(dian)力(li)相對減少,線損和發(fa)熱相應減少,一旦遭遇(yu)超設計標準的冰(bing)(bing)凍災(zai)害,容(rong)易發(fa)生覆冰(bing)(bing)倒塔。